public void Initialize()
        {
            var options = new DbContextOptionsBuilder <ApplicationContext>()
                          .UseInMemoryDatabase(databaseName: Guid.NewGuid().ToString())
                          .Options;

            _applicationUnitOfWork = new ApplicationContext(options);

            _applicationUnitOfWork.SeedMockCustomers();

            _applicationUnitOfWork.Database.EnsureCreated();

            var mappingConfig = new MapperConfiguration(mc =>
            {
                mc.AddProfile(new ApplicationMappingProfile());
            });

            IMapper mapper = mappingConfig.CreateMapper();

            _customerService = new CustomerService(_applicationUnitOfWork, mapper);
        }